Cognomen Thongkien (Thongkien 
) , all around the world, is an extremely rare last name. The last name Thongkien is characteristic of South-eastern Asia, particularly Thailand, where it is an extremely rare surname. Very seldom, Thongkien is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Thongkien | Thailand, United States |